The invention relates to the coupling and transmission of various types of analog and digital signals, including standard analog NTSC, SECAM, PAL and HDTV signals as well as serial digital versions thereof in complex television systems. These signals may be in electronic form or optical form and in either form may take on analog or digital form. In todays television technology, it is often necessary to route or couple television signals having many different formats throughout the television facility. Because of the use of many different formats, it has heretofore been required to utilize extremely wide bandwidth analog and separate parallel digital systems and cabling. This multiplicity of required equipment and cabling causes much complexity and cost in such systems.
1. Field of the Invention
The invention relates to the field of coupling and transmission of various types of analog and digital signals, and in particular analog and digital television video, audio, ancillary and control signals.
2. Description of the Prior Art
In many television facilities, it is necessary to provide large switching and routing networks in order to couple signals from the output of one particular source to the input of another particular processor or user of the signal. To perform these functions, large routing switchers and patch matrix panels provide matrix switching of signals utilized in the television facilities. Typically matrices of 128.times.128 are utilized which are capable of coupling any of the 128 input to any number of the 128 outputs in a completely arbitrary manner. Matrices larger than 128.times.128 are also used. These large matrices require a large number of individual switches, or crosspoints, with a 128.times.128 router requiring 16,384 such crosspoints.
Because of the use of many different formats, it has heretofore been required to utilize separate extremely wide bandwidth analog routers for analog signals and separate parallel digital routers for digital signals, with multiple versions of each such analog or digital systems and cabling being required due to the specialized needs of each type of signal used. For example, in a television station which uses 4 audio channels, i.e. stereo for two languages, analog time code, digital time code, PAL video in analog form, NTSC video in analog form and PAL or NTSC video in digital form, to implement 128.times.128 routing for all of these signals would require several times the previously mentioned 16,384 crosspoints, some of which are tailored to video, some to audio, etc. This multiplicity of required equipment and cabling causes much complexity and cost in such systems.